1. Field of the Invention
The invention relates to an image processing apparatus and an image processing method.
2. Description of the Related Art
Japanese Patent Application Publication No. 2003-15816 describes a face/line-of-sight recognition apparatus that detects the direction of the face and the line of sight of a user in real time by performing a series of processes, that is, face search, face tracking, blink detection, and line-of-sight direction determination, on the data of a user's face image picked up by a stereo camera. In this face/line-of-sight recognition apparatus, errors that cause wasted operation time are reduced to achieve high-speed image processing.
In the systems, such as pre-crash safety systems, in which real-time output of the image processing results is required, a series of processes must be completed within a predetermined period of time. However, even when errors are not occurring, the processing time of each process in image processing is not constant, but varies depending on, for example, the branching conditions and other interrupt processes (in particular, multiple interruptions) (see FIG. 8). Meanwhile, the importance and the required accuracy of a process vary depending on the process in many cases. Thus, also in view of the real-time processing and the required accuracy, it is difficult to say that it is efficient to indiscriminately perform all the processes.